Rerate Overview; Aerodynamic, Mechanical, Efficiency Considerations, Trends

This paper will take into consideration aerodynamic design, mechanical limitations, machine life assessment, and physical space limitations both inside the casing of the machine and on the compressor deck when a plant operator is considering new operating conditions for compressors and/or steam turbines.  It will help the operator determine whether it is more beneficial to rerate an existing machine, or replace it with a new drop-in machine. 

Additionally, the difference in the time it takes to install a rerate and the time it takes to install a new drop-in machine will be evaluated with an eye toward minimizing the duration of a plant turnaround.  The role of machine auxiliaries such as oil systems, buffer gas systems, injection systems, and control systems will also be explained.